Chapter 3 & 4 APCHEM Finals Review

If .40mol of H2 and .15 mol of O2 were to react as completely as possible to produce H2O, what mass o reactant would remain?

.20g of H2O

Free Response Question: 1) A 21,4 grams ample of lithium carbonate is added to 26.7 grams of aluminum nitrate to form a precipitant. 2) If 14.5 grams of the precipitant is formed, what is the percent yield for this reaction?

1) 3CO3- + 2Al^+3 Al2 (CO3)3 2) 98.6%

Free Response Question: 1) A liter of a 2.0 M solution of copper (II) nitrate is added to a lite of a 2.0M solution of lithium hydroxide and precipitate forms. 2) Draw a particulate representation for when equimolar of each reactant is reacted.

1) Cu^+2 + 2OH- Cu(OH)2 2) Li+ (X2) NO3- (X4) Cu+2 (X1) - bottom: Cu(OH)2

Free Response Question: 1)The equivalence point of a titration is reached using 24.5 ml of a 0.332M solution of sodium hydroxide and 45.80mL of hydrochloric acid. 2)What is the molarity of the hydrochloric acid?

1) OH- + H+ H2O 2) .178 M HCL

Free Response Question: 1)Magnesium reacts with solution of aluminum chloride. 2) Write the half reactions and identify the number of total electrons transferred in this reaction.

1)3Mg^0+2Al^+33mg^+3+2Al^0 2) 6e- + 2Al^+3 2Al^0 6 electrons transferred

A 2.0 mol sample of MgCl2(s) and .10 mol sample of of KCL (s) are dissolved in water and diluted to 500 mL. what is the concentration of Cl^-1 in the solution?

1.0 M

Which of the following is the balanced net ionic equation for the reaction between Li(s) and water?

2Li(s)+2H2O(l) 2Li+(aq) +2OH-(aq)+H2(g)

Which of the following diagrams best represents the AgNO3 solution before the reaction occurs? Note: water molecules are represented by the mickey symbol.

Ag+ has big circles towards it, NO3- has smaller circles towards it.

Beaker X and beaker Y each contain 1.0 L of solution, as shown above. A student combines the solutions by pouring them into a larger, previously empty beaker Z and observes the formation of a white precipitate. Assuming that volumes are additive, which of the following sets of solutions could be represented by the diagram above?

Beaker X: 2.0 M AgNo3/ Beaker Y: 1.0M MgCl2/ Beaker Z: .05 M Mg(NO302)and AgCl(s)

A sample of a compound that contains only the elements C, H, and N is completely burned in O2 to produce 44.0g of CO2, 45.0g H2O, and some NO2. A possible empirical formula of the compound is-

CH5N

If equal masses of the following compounds undergo complete combustion, which will yield the greatest mass of CO2?

Cyclohexane, C6H12

What is identity of metal chloride: Mass of unknown chloride, MCl: .74g , Mass of filter paper: .80g , Mass of filter paper plus AgCl precipitate: 2.23g

KCL

In which of the following compounds does sulfur have an oxidation state of +4?

SO3

During the course of the experiment, which of the following happens to the NO3- ions?

They remain dissolved in the filtrate solution.